Flavonoid and hydroxycinnamate profiles of english apple ciders.
ABSTRACT Seventeen phenolic compounds in 23 English apple ciders were identified and quantified by HPLC-PDA-MS (2). The total phenolic content of the ciders varied greatly ranging from 44 to 1559 mg/L. Four groups of compounds were identified, flavan-3-ols, hydroxycinnamates, flavonols, and dihydrochalcones. Hydroxycinnamates were the predominant group of phenolics in the majority of the ciders. Procyanidins were analyzed by HPLC after thiolysis, and total procyanidin content ranged from 8 to 722 mg/L and an average degree of polymerization of 2.5-3.5. This investigation of a wide range of ciders has shown a substantial variation in the profile and quantity of the phenolics. The analysis of single variety ciders highlighted the importance of using an apple cultivar with a high phenolic content to produce a phenolic-rich cider. Adaptations to the cider-making process could be used to increase the phenolic content with potential health benefits.
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ABSTRACT: BACKGROUND: Plums are a rich source of nutritive and bioactive compounds. The objective was to evaluate the impact of fruit tissue (flesh and peel), ripening stage and cultivar on the composition of phytochemicals in plums (Prunus domestica L.) and to analyse the relation between total antioxidant activity (TAA) and the measured variables. RESULTS: The content of total sugars and total organic acids was higher in flesh but total phenolic content (TPC) and TAA was statistically higher in plum peel. The composition of sugars depended on fruit tissue, ripening stage and the cultivar. Ripening and fruit tissue affected the composition and concentrations of organic acids. TPC of 'Haganta' peel increased during ripening but there was no significant time trend for 'Jojo' peel and flesh of both cultivars. The composition of phenolics in peel depended on the cultivar, but in flesh on the cultivar and ripening. Ripening resulted in increased total anthocyanins and TAA in peel. TAA(peel) was positively correlated with TPC(peel) , total anthocyanins(peel) , cyanidin 3-glucoside(peel) and peonidin 3-rutinoside(peel) in the cultivar 'Haganta'. CONCLUSION: The composition of phytochemicals in P. domestica fruit depends on fruit tissue, ripening stage and the cultivar. Peel contributes to the TAA on average 20 times more than flesh. Copyright © 2012 Society of Chemical Industry.Journal of the Science of Food and Agriculture 07/2012; · 1.88 Impact Factor
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ABSTRACT: Apples are the most widely consumed fruits in Germany and various other countries. Positive health effects of apple-derived polyphenols in vivo depend on their absorption, metabolism, distribution, and elimination from the body after consumption. Data on the metabolism of these polyphenols in humans are scarce. In order to study the intestinal transit and metabolism of apple polyphenols in humans, a variety of experiments were carried out. Polyphenols were incubated with saliva (for 5 min), simulated gastric or duodenal juice (4 or 10 h, respectively), or rat hepatocytes (4 h) under aerobic conditions, and with ileostomy fluid under aerobic conditions for 10 h. The polyphenol profile in human serum (8 h later) and renal elimination in urine (24 h later) were also investigated after consumption of 1 L apple juice. Polyphenols and their metabolites were identified and quantified by high-performance liquid chromatography with diode array detection (HPLC-DAD), HPLC-electrospray ionization-tandem mass spectrometry (ESI-MS/MS), and gas chromatography (GC)-MS. In the presence of native saliva or ileostomy fluid, β-glycosides of phloretin and quercetin were hydrolyzed, to varying degrees depending on the sugar moiety, and to much lesser degrees in the presence of antibiotics. In the gastric milieu, almost complete degradation of procyanidin B(2) to (-)-epicatechin was observed. In the presence of artificial duodenal juice flavan-3-ol epimerization occurred. Quercetin was completely converted to phloroglucinol, 3,4-dihydroxybenzoic acid, and 2,4,6-trihydroxybenzoic acid. Formation of isomeric products of hydroxycinnamic acid esters and their corresponding methyl esters was also observed, and similar results were obtained after incubation with rat hepatocytes. Products of phase II metabolism, two phloretin O-glucuronides and eight (methyl) quercetin O-glucuronides, were identified in the hepatocyte samples. Following enzymatic hydrolysis, 5-caffeoylquinic acid, 4-p-coumaroylquinic acid, caffeic acid, (-)-epicatechin, phloretin, and quercetin were recovered in both serum and urine (5.3% and 3.5% of the amounts consumed, respectively). In addition, 19.5% of the polyphenols consumed were identified in the urine in the form of hydroxylated phenolic and hippuric acids. The findings relating to the absorption, metabolism, and systemic availability of polyphenols in vivo should contribute to our understanding of their biological effects, and the characterization of newly formed metabolites should facilitate further studies.European Journal of Nutrition 12/2010; 50(7):507-22. · 3.13 Impact Factor
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ABSTRACT: A new, rapid, selective and sensitive ultrahigh performance liquid chromatography with diode array detection coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (UHPLC-DAD-ESI-Q-ToF-MS) strategy using automatic and simultaneous acquisition of exact mass at high and low collision energy, MS(E), has been developed to obtain polyphenolic profile of apples, apple pomace and apple juice from Asturian cider apples in a single run injection of 22min. MS(E) spectral data acquisition overcomes chromatographic co-elution problems, performing simultaneous collection of precursor ions as well as other ions produced as a result of their fragmentation, which allows resolving complex spectra from mixtures of precursor ions in an unsupervised way and eases their interpretation. Using this technique, 52 phenolic compounds of five different classes were readily characterized in these apple extracts in both positive and negative ionization modes. The spectral data for phenolic compounds obtained using this acquisition mode are comparable to those obtained by conventional LC-MS/MS as exemplified in this work. Among the 52 phenolic compounds identified in this work, 2 dihydrochalcones and 3 flavonols have been tentatively identified for the first time in apple products. Moreover, 2 flavanols, 4 dihydrochalcones, 9 hydroxycinnamic acids and 4 flavonols had not been previously reported in apple by ToF analysis to our knowledge.Journal of Chromatography A 09/2013; · 4.61 Impact Factor